N4792D accident description

NTSB description

On July 14, 2006, about 1745 eastern daylight time, a Cessna 172N, N4792D, was destroyed during a forced landing and collision with trees, after experiencing a loss of engine power in cruise flight near Pompton Lakes, New Jersey. The certificated private pilot was fatally injured. Visual meteorological conditions prevailed for the flight that departed Essex County Airport (CDW), Caldwell, New Jersey, about 1700. No flight plan was filed for the local personal flight conducted under 14 CFR Part 91.

According to recorded radio communications from the CDW air traffic control (ATC) tower, the pilot contacted the CDW tower prior to the accident. The pilot stated that the airplane was north of the Wanaque Reservoir, and that he had no throttle control. The pilot further stated that the engine rpm was 1,400, and that the airplane was losing altitude. The air traffic controller then asked the pilot if he was declaring an emergency, and the pilot replied yes. The controller asked the pilot his intentions, and the pilot replied that he was crossing Route 287, at 700 feet, and losing altitude. The pilot further stated that he was going to try and divert to Lincoln Park, New Jersey, but did not think that he would make it. The controller then stated that if the pilot could find an area large enough to land, to please advise him, and the controller would notify the police. No further communications were received from the pilot.

The pilot attempted a forced landing to an access road; however, the airplane struck trees and a postcrash fire ensued.

The accident occurred during the hours of daylight. The wreckage was located approximately 41 degrees, 01.00 minutes north latitude, and 74 degrees, 16.80 minutes west longitude.

The pilot held a private pilot certificate, with a rating for airplane single engine land. His most recent Federal Aviation Administration (FAA) third class medical certificate was issued on April 12, 2005. The pilot's logbook was not recovered; however, review of FAA records and the airplane operator's rental history, revealed that the pilot had accumulated an estimated total flight experience of approximately 340 hours. According to the rental history, the pilot had flown approximately 4 hours during the 30 days preceding the accident, and 9 hours during the 90 days preceding the accident. All of the pilot's flight experience, from January 2005, was in the same make and model as the accident airplane.

The wreckage was examined at a salvage facility on July 26, 2006. The engine was found removed from the airframe. The throttle body portion of the carburetor remained attached to the engine, and the cotter pin was missing from the throttle lever locknut. The throttle lever locknut was partially backed-off its stop. In addition, the throttle lever was loose, and the serrations on the throttle shaft stop were disengaged from the serrations on the throttle lever.

The starter, oil pump, magneto drive, oil filter, baffling, propeller, exhaust system, and firewall were removed from the engine. The magnetos were destroyed by fire. The oil filter was opened, and no metallic contamination was observed.

The valve covers were removed from the engine, and oil was observed throughout the engine. The top sparkplugs were removed, their electrodes were intact, and gray in color; except for the number one and three sparkplugs, which were oil soaked. The crankshaft was rotated via the oil pump accessory gear drive, using a socket wrench. Crankshaft, camshaft, and valve train continuity were confirmed throughout the engine, and thumb compression was attained on all cylinders.

Flight control continuity was confirmed from the left and right wing aileron bellcranks, to the wing roots where the cables were cut during recovery. Continuity was also confirmed from the elevator and rudder, to where they were cut about the mid-cabin area, and then continued to the control "T" and rudder pedals. The elevator trim actuator jackscrew measured approximately 1.35 inches, which corresponded to 4 to 5 degrees nose-down pitch.

Review of the maintenance records revealed that the accident flight was the first flight after the airplane's most recent annual inspection was completed. At the time of the inspection, the airplane had accumulated about 10,675 hours of operation. During the annual inspection, the throttle shaft bushings and shaft assembly were noted as worn, and were subsequently removed and replaced.

After the accident, the mechanic that performed the annual inspection was interviewed via telephone. The mechanic stated that he recalled installing a throttle shaft bushing and a throttle shaft, but did not recall a cotter pin missing.

Review of a Cessna "Model 172 Series Service Manual" revealed instructions and diagrams to secure the locknut with a cotter pin.

An autopsy was performed on the pilot by the Passaic County Regional Medical Examiner's Office, Newark, New Jersey.

Toxicological testing was conducted on the pilot at the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma. Review of the toxicology report revealed: